LXR linux/arch/mips/loongson64/dma.c

   1// SPDX-License-Identifier: GPL-2.0
   2#include <linux/dma-direct.h>
   3#include <linux/init.h>
   4#include <linux/swiotlb.h>
   5#include <boot_param.h>
   6
   7dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
   8{
   9        /* We extract 2bit node id (bit 44~47, only bit 44~45 used now) from
  10         * Loongson-3's 48bit address space and embed it into 40bit */
  11        long nid = (paddr >> 44) & 0x3;
  12
  13        return ((nid << 44) ^ paddr) | (nid << node_id_offset);
  14}
  15
  16phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr)
  17{
  18        /* We extract 2bit node id (bit 44~47, only bit 44~45 used now) from
  19         * Loongson-3's 48bit address space and embed it into 40bit */
  20        long nid = (daddr >> node_id_offset) & 0x3;
  21
  22        return ((nid << node_id_offset) ^ daddr) | (nid << 44);
  23}
  24
  25void __init plat_swiotlb_setup(void)
  26{
  27        swiotlb_init(1);
  28}
  29